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Altera_Forum
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16 years ago

cycloneIII EP3C25E144 I/O pins

I'm using CycloneIII EP3C25E144 FPGA for my design .In cycloneIII brochure the no of I/O's available for the specific FPGA is mentioned as 82 but in the pin description table I could find only 65 I/O pins. Please let me know if I can use the CLK[0..15] pins as optional I/O pins.

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  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    --- Quote Start ---

    Please let me know if I can use the CLK[0..15] pins as optional I/O pins.

    --- Quote End ---

    They can be used as general input pin. Unlike standard I/O pins, they don't have a weak pull-up or hold option, so they shouldn't be left unterminated.

    Generally, the pin-out files for individual Cyclone III types have the most detailed information about functionality of each pin. Quartus Pin Planner also knows about available pin features.